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./7/-75 749545. l v ./QQf/ii/.a-ZZ@ 7555- l N w mgm M5 N n R l um] I lA-I- @A Lf. m n: n L@ Eri UNITED STATES PATENT. OFFICE.

HENRY S. HOPKINS," OF PROVIDENCE, RHODE ISLAND, ASSIGNOR TO HOPKINS,

HENDRICK & PEOKHAM.

MEANS FOR'REGULATING- VARIABLE CUT-OFFS FOR STEAM-ENGINES.

Specification of Letters Patent No. 14,545, dated March 25, 1856.

T0 all whom t may concern.'

Be it known that I, HENRYV S.' HOPKINS, of Providence, in the county of Providence and State of Rhode Island, have invented an Improvement in Mechanism for Regulating the Operations of a Cut-Off Valve or Mechanism of a Steam-Engine, my invention being an improvement on mechanism for which a patent has been granted George I-I. Oo'rliss; and I do hereby declare that the same is fully described and represented in the following specification and the accompanying drawings, of which- Figure l, exhibits a front view or elevation of the machinery to which my improvement is applied. Fig. 2, is a plan of the same.

In these drawings, A, denotes a slide rod, which when in use is moved forward and backward longitudinally by a ball governor. It is fastened to an inclined cam or plane B, which rests against the upper end of a vertical slide bar C, whose foot is supported on a movable catch, I), by which the crank E, of the shaft F of the cut oftl valve is moved and liberated. There is attached to an arm Gr, extending from said crank, a weight, I, by which the cranks is moved in an opposite direction, after it has been liberated from the catch rod. The said catch rod is pressed up to the vertical slide by means of` is an end view of the mechanism, and has a shape in transverse section as shown by the red line in Fig. 1, the same being made to operate in connection with a catch notch, a, of the catch rod before described.

When the engine is going at too great a speed, the ball governor (which is not represented in the drawings, as its application to and mode of operation of the slide rod is well understood by those who are acquainted with the said mechanism of the said Corliss, and which is described in his Patent Numbered 6162) will draw the inclined plane toward the right so as to depress the vertical slide and thereby cause the catch bar to be sooner liberated from the 'catch pin of the valve crank, so that when the engine is moving too slow, the inclined plane will be moved in an opposite direction, and the catch rod will be longer in being liberated from its pin. In'the'action of the vertical of liberation of the catch .pin it serves as a fulcrum or bearer Vto the catch lever during its longitudinal and vertical movements produced by the rocker lever, the action of such parts being well understood.

Having thus referred to that part yof the invention of Corliss, on which my improvement is grafted, I would remark that with the mechanism of Corliss there is much liability to accident from accelerated motion which may result in case the driving belt of the regulator or ball governor should acci-- dentally slip from its pulley or should there be any defect in the actionof thev regulator. For should the motion of the regulator cease and its balls fall into their lowest position, it will readily be seen that the inclined plane will be moved toward the left so as to allow the slide bar to rise suddenly to its greatest height and consequently the speed of the engine would be immediately and greatly accelerated owing to the increased flow of steam into the cylinder, which would necessarily result. In order to arrest the motion of the engine, or in other Words to prevent the catch bar from operating the valve crank in case of any such improper action of the regulator or ball governor, as

vabove described. I combine with t-he main inclined plane B, a secondary reversed inclined plane, S, which I arrange with respect to it as shown in Fig. 1. During the fall of the balls or arms of the governor, this secondary inclined plane will be moved into contact with the vertical slide and -force it downward into position, as shown in Fig. 4, which is a front elevation of thek mechanism as it appears under such circumstances. In this case, the catch rod will be depressed so far as to be thrown entirely out of action with its crank pin, during the longitudinal movements of said catch rod: Thus the en-` gine will stop in consequence of the steam being entirely cut off from its cylinder.

In order that the steam may not be entirely cut off, whenever it may be desirable to stop the engine, under ordinary circumstances, I make use of a movable or shifting stop or block, T, which is formed as seen in Fig. 1, and also in Fig. 4, (which is an end view of said stop). yIt is made so as to slide, either to quicken or prolong the time Y straddle the rod A, and to eXtend from the foot of the inclined plane B, to the shoulder piece, m. It prevents the reversed inclined plane, S, from being driven over the vertical slide, C. Just previous to stopping the steam engine, the engineer puts the stop, T, in place, and after the engine has been start ed or set in motion, he should remove the stop so as to allow the reversed inclined plane to be brought into action under circumstances as above specified.

What I claim as my invention or improvement, is-

l. Combining the reversed inclined plane S, with the main inclined plane of the regu- 

